Shedding mechanism for looms



Nov. 9, 1954 P. A. NIMS SHEDDING MECHANISM FOR LOOMS 2 Sheets-Sheet 1 so N INVENTOR PHILIP A. NIMS Filed Feb. 20. 1953 ATTORNEY Nov. 9, 1954 I p, ms 2,693,828

SHEDDING MECHANISM FOR LOOMS Filed Feb. 20, 1953 2 Sheets-Sheet 2 FIG. 2

INVENTOR PHILIP A. NIMS ATTORNEY United States Patent SHEDDING MECHANISM FOR LOOMS Philip A. Nims, Worcester, Mass,

ton & Knowles Loom Works, corporation of Massachusetts assignor to Cromp- Worcester, Mass., a

This invention relates to improvements in shedding mechanisms for looms and it is the general object of the invention to provide a simplified means for leveling the warp controlling harness frames.

In the operation of a loom it is occasionally desirable to bring all of the warp threads to a single plane either to make a pickout or check the draft of the warp threads through the reed. In certain types of shedding mechanism, such as a dobby or a head motion, this is a simple operation, but looms wherein the harness frames are operated by cams do not employ pattern controlled fingers or vibrators which facilitate leveling in dobbies or heads and some difficulty is encountered in moving the harness frame operating levers to a common position for the leveling operation.

It is an important object of the present invention to provide a simple form of lock means for the harness operating levers utilizing individual locks for the levers so controlled that when leveling is desired the locks can move into lever locking position whenever the levers are moved to a given extreme position by their cams.

It is a further object of the invention to provide controller means ordinarily positioned to prevent the locks from moving to locking position but movable to allow the locks to move toward locking position. As shown hereinafter this controller means for the locks may be in the form of a counterweight associated with each lock.

After all of the locks are in locking position certain of the levers will not be on the high areas of their cams and will tend to move toward their low cam areas, thereby exerting return of the locks from locking to non-locking position. It is a further object of the invention to arrange the aforesaid counterweights so that they can all be moved to a position in which they will exert a force on the locks tending to move the latter to non-indicating position. The locks which are held by their levers will not be able immediately to move to lever releasing or non locking position, but if the loom is caused to operate for a few successive picks all of the locks will eventually be released because have been moved by the high areas of their cams, whereupon the connterweights are able to move the previously held locks away from their levers.

When it is desired to change the order of the cams or replace certain of them with other cams the difliculty arises that certain at least of the levers will be held against the. cams in such a manner as to make removal of the cams inconvenient even though all the locks are in locking position. It is a still further obiect of the invention to provide means by which all of the locks, after they have been moved to locking position, can be given a motion in a direction to move the levers away from the cams. The cams can then be slid endwise from their supporting shaft without interference on the part of the levers.

It is a further object of the invention to provide an improved method for manipulating a cam harness mo tionvso that after the loom has operated for a given sequence of picks all of the locks will have had opportunity to move automatically into locking position with respect to their levers due to the fact that each lever will bemoved to its extreme position at least once during the sequence.

A still further object is to provide an additional step for the aforementioned method wherein, preferably by a manual operation, all of the locks can be moved in forces on their locks which interfere with of the fact that their levers will 7 supported as at 8 to parts 9 of the loom frame.

. different angular rality of harness cams 27.

2,693,828 Patented Nov. ,9, 1954 a direction to disconnect or detach the levers from their cams, thereby simplifying removal and replacement of the latter.

In order that the invention may be clearly understood reference is made to the accompanying drawings which illustrate by way of example two embodiments of the invention and in which:

Fig. l is a front elevation showing part of a loom having the preferred form of the invention applied thereto, I

Fig. 2 is an enlarged plan view looking in the direction of arrow 2, Fig. 1,

Fig. 3 is an enlarged vertical section on line 3-3, Fig. 2, showing a lock and its counterweight in two different positions,

Fig. 4 is a detail transverse section through the upper end of one of the harness levers taken on line 44, Fig. 3,

Fig. 5 is a fragmentary plan view looking in the direction of arrow 5, Fig. 3,

Fig. 6 is a vertical section on line 6-6, Fig. 5,

Figs. 7 and 8 are diagrammatic views illustrating the manner of operation of the invention,

Fig. 9 is a diagrammatic view similar to the dotted line position shown in Fig. 3, but illustrating a modified form in which the harness levers can be moved away from their cams, and P Fig. 10 is an enlarged vertical section on line 10-10,

Referring particularly to Fig. l, the loom frame 1 comprises right and left hand loomsides 2 and 3, respectively, each of which has secured thereto a harness frame guide 4. Each guide has a vertical guideway 5 in which the adjacent ends of harness frames 6 move. Each harness frame is connected to pulldown spr if lgs e springs tend normally to move the harness frames to low position to form the bottom warp shed, but the springs can be stretched to permit upward movement of the harness frames when they are to form the top warp shed.

Included in the loom frame is a cross girt 10 supporting bearings 11 on which are mounted pins 12 each of which rockably supports a plurality of bell crank levers 13. The latter levers are arranged in pairs, each pair being connected by upright lifter rods 14 to one of the harness frames. As shown in Fig. l certain ofv the bell crank levers have been rocked to cause upward motion of their associated harness frames while other of these levers have been rocked to, permit the pull-down springs to lower the corresponding harness frames.

The means for operating the bell crank levers includes a series of rods 15 extending horizontally along the lower part of the loom. Each rod is connected to a pair of bell crank levers 13 so that longitudinal motion of any rod will produce vertical motion of the associated harness frame. connected to harness frame lifting levers 16pivoted on a stationary rod 17 supported by a bracket 18 secured to the loomside 3, see Fig. 2. The upperarm 20 of each of the levers 16 has secured to opposite sides thereof plates 21. which are secured to the lever by rivets or the like 22. Each pair of plates extends abovethe adjacent upper end of the corresponding lever 20 and is bridged by a holding pin or stud 23 which is located above the top of the associated lever 16. The bracket 18 has secured thereto arms 24 for a purpose to be described.

The bracket 18 supports a shaft 25 turning in bearings 26 on the bracket and having secured thereto a pluleast one low area 30 and at least one high area 31 to engage one of the harness frame lifting levers 16. A

beveled gear 32 secured to shaft 25 meshes with a beveled pinion 33 secured to a shaft 34 which rotates during loom operation. During loom operation each lever 16 will engage the high and low areas of its cam at least once during a given sequence of picks.

As shown in Fig. 2 there are eight cams and eight levers 16, and the cams have their high and low areas in positions so that as the shaft 25 ro- The left hand ends of the rods are Each of the cams has at tates certain harness frames will be down and others up for each pick of the loom. Each lever 16 has a roll 35 rotatable between the two plates 21 of the lever 16 and against its cam by the springs 7 of the associated harness frame. The .rolls can, however, be moved away from the cams as will appear hereinafter.

The matter thus far described sets forth a known form of cam harness motion to which the invention to be described hereinafter may be applied.

Referring more particularly to Figs. 2 and 3, the arms 24 support a pivot support or rod 40 on which are pivoted a plurality of stops or locks 41, one for each lever 16. Each stop or lock has an abutting end 42 for engagement with the stop stud 23 of the corresponding lever 16 and has a finger 43 for engagement with a limiting or stop rod 44 also supported by the arms 24 and extending parallel to the'pivot rod 40.

Also provided on the rod 40 are counterweights 45, one for each lock 41. Each lock has a lateral lug 46 having upper and lower abutting faces 47 and 48, respectively, and each counterweight has a lateral lug 49 having an abutting face 50 to engage the face 47 and having also an abutting face 51 to engage the face 48, see Fig. 6.

In the normal operation of the loom the counterweights, which act as controller means for the locks, will be in the normal controlling position shown in full lines, Fig. 3, being held in this position by their engagement with rod 44. The abutting face 51 of each counterweight engages the abuttingxface 48 of the corresponding lock 41 and the latter is held in its normal non-locking position shown in full lines in Fig. 3 due to the greater weight of the counterweight 45. The locks all tend, however, to move toward lever locking position. When it it desired to level the harnesses all of the counterweights will be moved from the full line position on one side of the pivot support 40 to the noncontrolling dotted line position shown in Fig. 3 on the other side of rod 40, thereby moving the abutting face 51 away from the faces 48 and releasing the locks so that they can fall to the dotted line position shown in Fig. 3 with their fingers 43 against rod 44. The locks are so positioned that they register with their studs 23 and the space between the plates 21 of their corresponding levers 16.

Certain of the cam levers 16 will usually be engaged with the high areas of their corresponding cams when the loom is stopped and the stops 41 corresponding to these levers will fall immediately into locking relation with respect to their studs 23 and levers 16 to lock the latter in the extreme position A, Fig. 3. Other of the levers 16 will be in engagement with the low areas of their cams and will be in the position B, Fig. 3, see also Fig. 7. As the loom is then operated, preferably though not necessarily one pick at a time, these other levers will eventually be moved to the extreme or common position A, and in moving to that position their studs 23 will temporarily lift the corresponding locks 41. When these levers finally reach position A the associated locks will fall to locking position. At the end of the sequence of successive picks of the loom, therefore, all of the levers 16 will have been moved to the extreme position A, Fig. 3, by the high areas of their cams and all of the locks will be in locking position. At this time all of the harness frames will be at the same level.

When it is desired to return the loom to normal condition the counterweights will be swung back from the dotted line to the full line position, Fig. 3. Those locks corresponding to levers which happen to engage high areas of their cams at this time will be immediately returned to their normal non-locking position by their counterweights, or will move to the full line position shown in Figs. 3 and 8. Certain other of the levers which would normally be engaging low areas of their cams will be held against their locks by the corresponding pull-down springs 7, and will prevent their locks from returning immediately to normal non-locking position. The counterweights of these locks last described will be in the dotted line position shown in Fig. 8, exerting an upward force on the locks but not being able to lift the locks. As the loom is run pick by pick during the next sequence of picks, however, the high areas of the cams corresponding to the levers which have been spring held against their locks will be moved to the extreme position A by high areas of their cams and when this happens the counterweights can fall from the dotted line to the full line position, Fig. 8, thereby lifting their associated locks to normal non-locking position. The shedding mechanism will then be back in normal condition and weaving can be resumed.

It is occasionally necessary to remove the cams 27 from the shaft 25 and either rearrange them with respect to their order on the shaft or replace them with other cams. During this operation it is desirable that the levers 16 be held out of contact with the cams so that the latter can slide endwise of the shaft without interference on the part of the levers. In order to achieve this result a modification may be employed such as shown in Figs. 9 and 10. The purpose of this modification is to enable all of the locks 41 to be moved bodily in a direction which will move their respective levers away from the cams after all of the levers have been previously locked in the extreme position A.

As shown more particularly in Fig. 10 the pivot support or rod 44 is replaced by a shaft 60 having gudgeons 61 at the end thereof one of which is shown in Fig. 10. These gudgeons are mounted for rocking motion on the arms 24 and one of the gudgeons is extended to have a handle 62 secured thereto by a key 63. The main part 64 of the shaft 60 between the gudgeons is of somewhat larger diameter than the gudgeons and is eccentric with respect to them. Locks 41a and counterweights 45a similar to parts 41 and 45, respectively, already described, are mounted for angular motion on the eccentric part 64 of shaft 60.

During a normal leveling operation such as previously set forth the handle 62 will be in the full line position shown in Fig. 9 and the procedure already described for leveling the harnesses will be carried out with the handle in this position. If, however, it is desired to remove the cams, the stops and counterweights will first be swung to the full line position shown in Fig. 9 and the procedure already described will be followed until all the levers are locked in their extreme position. The handle 62 will then be moved to the dotted line position, Fig. 9, to cause the eccentric part 64 of shaft 60 to act :as a shifting means to move the locks and levers engaged by them from the full line to the dotted line position, Fig. 9. The result of this operation is to move the rolls 35 bodily away from their cams so that the latter can be removed without interference by the levers 16. Stops 65 and 66 on one of the arms 24 act to limit motion of the handle 62 and the eccentric.

In the event that the loom is to be run with less than its full harness capacity it may be desirable, if the unused cams are left on the shaft 25 instead of being removed from it, to provide for holding the unused harness levers 16 out of engaging position with respect to their cams. In that event the handle 62 can be moved to the dotted line position, Fig. 9, and those stops 410 corresponding to the unused levers can be used to hold the latter away from the high points of their cams. The counterweights and stops for the levers which are used will be in their normal non-locking position, the eccentric part 64 of the shaft 60 serving under these conditions the same purpose as does pivot support or rod 40 in the preferred form.

From the foregoing it will be seen that the invention sets forth a simple form of lock means for the harness frame operating levers of cam looms wherein a leveling operation can be performed merely by swinging the counterweights from their normal to their lock releasing position, that is, from the full line to the dotted line position, Fig. 3, and then operating the loom a suflicient number of picks to move all of the levers to their extreme position A at least once, thereby enabling all of the stops to move to lever stopping position. It will also be seen that at the end of a given sequence of picks certain of the locks 41 will be held against free motion by their levers 16 due to action of the springs 7, but continued running of the loom will effect releasing of these locks as their levers move to the extreme position A and the counterweights can then complete their return motion to normal position by moving from the dotted line to the full'line position shown in Fig. 8. Also, when it is desired to move all of the levers out of engaging position with respect to the cam the procedure for leveling will first be followed and then the handle 62 can be moved from the full line to the dotted line position, Fig. 9, to give the levers 16 a slightly additional motion which will move their rolls 35 out of engaging position with respect to the earns 27. The invention also sets forth a method of leveling wherein stops are positioned to move automatically into locking position whenever the levers are in an extreme position, the loom being run for a sequence of picks during which all of the levers will move at least once to the extreme position to permit all of the stops to move to locking position. A further method contemplates the additional movement of all of the stops to move their levers out of engagement with the cams.

Having now particularly described and ascertained the nature of the invention and in what manner the same is to be performed, what is claimed is:

1. In shedding mechanism for a loom having a plurality of harness frame operating levers all of which move to a given extreme position at least once during a given number of successive picks of the loom, a plurality of lever locks, one for each lever, tending to move to locking position relative to their respective levers, and controller means for said locks normally preventing the locks from moving to locking position but movable to release said locks, whereupon said locks move toward locking position, the locks corresponding to the levers in said given extreme position moving immediately into locking position to hold their levers in said extreme position, and

the remaining locks moving to locking position relative to their levers as the latter reach said extreme position in said given number of picks and thereupon holding their levers in said given extreme position.

2. The shedding mechanism set forth in claim 1 wherein said locks are gravity actuated and fall toward and into locking position.

3. In shedding mechanism for a loom having a plurality of harness cams which rotate during loom operation and a harness lever for each cam to engage and have the position thereof determined by high and low areas of the cams, a plurality of locks, one for each lever, tending to move to lever locking position, and counterweight means for each lock movable to either of two positions, each counterweight means when in one position thereof preventing the associated lock from moving to locking position but when in the other position thereof enabling the associated lock to move toward locking position, the locks corresponding to levers positioned by high areas of their cams moving to locking position and the remaining locks, moving to locking position as their levers are positioned by high areas of their cams as the latter rotate during operation of the loom.

4. The shedding mechanism set forth in claim 3 including shifting means to move all of said locks when the latter are in. locking position in a direction to move the levers away from the cams.

5. In shedding mechanism for a loom having harness frames and including cams moving during loom operation and having high and low areas to engage levers operatively connected to the harness frames, a lock for each lever tending normally to move toward locking position relative to its lever, and a counterweight controlling each lock movable to either of two positions in one position of which the counterweight prevents the lock from moving to locking position and in the other position of which the counterweight permits the lock to move to locking position, provided the lever therefor is positioned by a high area of the associated cam.

6. In shedding mechanism for a loom having harness frame lifting levers and including cams moving during loom operation and having high and low areas to engage the levers, a lock for each lever tending normally to move toward locking position relative to its lever, and a pivoted counterweight controlling each lock swingable to either side of its pivot and when one side of the pivot acting to prevent the lock from moving to locking position but when on the other side of the pivot enabling the lock to move toward locking position, each lock being capable of moving to locking position relative to its lever provided the latter is engaged by a high area of the associated cam.

7. In shedding mechanism for a loom having harness frames and including rotary cams having high and low areas to engage levers operatively connected to the harness frames, yielding means tending to move each lever toward the low area of its cam, each lever engaging the high and low areas of its cam at least once during a normal given sequence of successive picks of the loom and certain of said levers normally engaging the low areas of their corresponding cams at the end of said given sequence of picks, a lock for each lever tending to move toward locking position with respect to its lever, and controller means elfective when in normal position to exert a yielding force on said locks tending to move the latter away from locking position and preventing said locks from moving toward locking position but movable to releasing position to enable said locks to move toward locking position, whereupon the locks move to locking position relative to their levers as the latter are positioned by the high areas of their cams during said sequence and all the locks are in locking position at the end of said given sequence of picks, said certain levers at the end of said sequence being held against their locks by said yielding means, said controller means when returned to normal position exerting said yielding force on all of said locks and effective during the next repetition of said given sequence to move from locking position those locks which were engaged with said certain levers at the end of said sequence as said certain levers engage the high areas of their cams.

8. In shedding mechanism for a loom having a plurality of harness frame lifting levers all of which move to a given extreme position at least once during a given number of successive picks of the loom, a plurality of lever locks, one for each lever, and controller means movable to controlling or noncontrolling position and when in controlling position preventing the locks from moving to locking position relative to their levers, said locks when the controller means is in non-controlling position tending to move to locking position relative to their levers and each lock being capable of moving to locking position relative to its lever when the latter is in said given extreme position, any lever not in said extreme position at the beginning of said sequence eventually moving to said extreme position by the end of said sequence to the end that all of said locks will be in locking position at the conclusion of said given sequence.

No references cited. 

